Fix clippy warnings

src/back/lto.rs

@@ -41,8 +41,8 @@ use crate::back::write::save_temp_bitcode;
 use crate::errors::{DynamicLinkingWithLTO, LtoBitcodeFromRlib, LtoDisallowed, LtoDylib};
 use crate::{GccCodegenBackend, GccContext, SyncContext, to_gcc_opt_level};
 
-/// We keep track of the computed LTO cache keys from the previous
-/// session to determine which CGUs we can reuse.
+// We keep track of the computed LTO cache keys from the previous
+// session to determine which CGUs we can reuse.
 //pub const THIN_LTO_KEYS_INCR_COMP_FILE_NAME: &str = "thin-lto-past-keys.bin";
 
 pub fn crate_type_allows_lto(crate_type: CrateType) -> bool {

src/intrinsic/simd.rs

@@ -375,7 +375,7 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
         // Make sure this is actually a SIMD vector.
         let idx_ty = args[2].layout.ty;
         let n: u64 = if idx_ty.is_simd()
-            && matches!(idx_ty.simd_size_and_type(bx.cx.tcx).1.kind(), ty::Uint(ty::UintTy::U32))
+            && matches!(*idx_ty.simd_size_and_type(bx.cx.tcx).1.kind(), ty::Uint(ty::UintTy::U32))
         {
             idx_ty.simd_size_and_type(bx.cx.tcx).0
         } else {

src/lib.rs

@@ -27,6 +27,8 @@
 // Some "regular" crates we want to share with rustc
 extern crate object;
 extern crate smallvec;
+// FIXME: clippy bug: remove the #[allow] when it's fixed.
+#[allow(unused_extern_crates)]
 extern crate tempfile;
 #[macro_use]
 extern crate tracing;